In this research, pyrolysis and combustion behavior of three different oil shale samples from Turkey were characterized using thermal analysis techniques (TG/DTG). In pyrolysis experiments, two different mechanisms causing mass loss were observed as distillation and cracking. In combustion experiments, two distinct exothermic peaks were identified known low and high temperature oxidation. On the other hand, determination of activation energies are required for the estimation of oil extraction conditions from the oil shales. Differential methods are used to determine the activation energies of the samples where various f(alpha) models are applied from the literature. It was observed that the activation energies of the all oil shale samples are varied between 13.1-215.4 kJ mol(-1) in pyrolysis and 13.1-408.4 kJ mol(-1) in combustion experiments which are consistent with other kinetic results.